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Maternal and fetal death associated with acute pancreatitis during pregnancy:A case report

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World Journal of Clinical Cases 2025年第10期13卷 53-58页

作者： Jin Li Qing-Yan zhang Mei-hong zhang Shan-Yun Jiang Department of Anesthesiology Kaihua County People’s HospitalQuzhou 324300Zhejiang ProvinceChina Center for Clinical Inspection and Quarantine Kaihua County Center for Clinical Inspection and QuarantineQuzhou 324300Zhejiang ProvinceChina

BACKGROUND Acute pancreatitis in pregnancy is a rare but serious condition that can lead to high maternal mortality and fetal *** of pregnancy complicated by severe acute pancreatitis,particularly with subsequent respiratory and cardiac arrest,are rarely *** SUMMARY We present the case of a 35-year-old woman,at 36+5 weeks of gestation,who presented with paroxysmal epigastric pain accompanied by low back pain,nausea,and *** to the clinical symptoms,B-ultrasound imaging and biochemical indicators,the patient was diagnosed with acute pancreatitis and initially managed ***,3 hours after admission,the patient experienced respiratory and cardiac arrest,and the fetus *** this case,the adverse outcomes occurred due to the lack of aggressive fluid resuscitation and an active surgical *** Implementing aggressive fluid resuscitation to sustain tissue perfusion,alongside the proactive evaluation of pharmacological agents that suppress gastric acid secretion and inhibit pancreatic enzyme activity,may be beneficial in mitigating the risk of a severely adverse *** management of acute pancreatitis during pregnancy requires careful timing of surgical intervention,a thorough evaluation of the risks and benefits regarding the continuation or termination of pregnancy,and a focus on safeguarding both maternal and fetal health.

关键词： Severe acute pancreatitis Pregnancy Cardiac arrest Fetal death Case report

An extended stress-based method for orientation angle optimization of laminated composite structures

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Acta Mechanica Sinica 2011年第6期27卷 977-985页

作者： Jin zhang Wei-hong zhang Ji-hong Zhu Engineering Simulation and Aerospace Computing （ESAC） The Key Laboratory of Contemporary Design ＆ Integrated Manufacturing Technology Northwestern Polytechnical University 710072 Xi＇ an China

Orientation optimization plays an important role in the lay-up design of composite *** orientation optimization methods face the main problem of huge number of design ***,a patch concept is proposed to reduce the number of design ***,the traditional stress-based method can not deal with patch orientation optimization of composite *** this paper,we propose an extended stress-based method to deal with such *** considered problems are to minimize the mean compliance under multiple load cases or to maximize the eigenvalues of a composite *** numerical examples are solved to demonstrate the efficiency of the new *** is shown that the new method has the ability to deal with constraints on orientation angle,such as symmetric,antisymmetric and discrete orientation angle *** iteration is less time-consuming because no sensitivity analysis is needed and a quick convergence rate can be achieved.

关键词： Structural optimization Composites Laminates Orientation angle optimization

Square Distance Symmetric Co-occurrence Matrix Thresholding Method Based on Relative Homogeneity

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Chinese Journal of Electronics 2020年第4期29卷 686-692页

作者： zhang hong FAN Jiulun Xi'an University of Posts and Telecommunications Automatic Sorting Technology Research Center State Post Bureau of the People's Republic of China

We studied a novel image thresholding method using symmetric co-occurrence matrix probability information, in which, the relative homogeneity characteristics of the segmented object and background is explored, square distance co-occurrence matrix thresholding criterion is reformed, and the relative criterion of square distance symmetric co-occurrence matrix is *** new thresholding method applies the spatial information of image and takes the relative information between classes into *** experimental results show that,comparing with the existing correlation methods, the proposed method can extract the object more integrity,and reserve the edge more clearly.

关键词： Image thresholding Symmetric Cooccurrence Matrix Square distance Relative homogeneity

Entry,egress and vertical transmission of SARS-CoV-2

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Journal of Molecular Cell Biology 2021年第3期13卷 168-174页

作者： Hui zhang hong zhang National Laboratory of Biomacromolecules CAS Center for Excellence in BiomacromoleculesInstitute of BiophysicsChinese Academy of SciencesBeijing 100101China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China

The high infectivity and pathogenicity of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)have caused the COVID-19 outbreak,one of the most devastating pandemics in more than a *** pandemic has already left a trail of destruction,including enormous loss of life,a global economic slump,and widespread psychological *** assiduous world-wide endeavors,an effective cure for COVID-19 is still ***,infected neonates and children have relatively mild clinical manifestations and a much lower fatality rate than elderly *** studies have unambiguously demonstrated the vertical transmission of SARS-CoV-2 from infected pregnant women to fetuses,which creates yet another challenge for disease *** this review,we will summarize the molecular mechanism for entry of SARS-CoV-2 into host cells,the basis for the failure of the lungs and other organs in severe acute cases,and the evidence for congenital transmission.

关键词： SARS-CoV-2 COVID-19 ACE2 TMPRSS2 placental transmission

Structure-property relationship of potassium titanyl (KTP)isomorphous substituted crystal

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Chinese Science Bulletin 1998年第7期43卷 529-536页

作者： Kecong zhang hong zhang Beijing Polytech Univ Dept Environm Chem & Engn Beijing 100022 Peoples R China

KTiOPO-4(KTP) crystal is a nonlinear optical material with superior properties. The KTP structure, point group mm2, is typified by the chemical form {K++}〔Ti 4+〕O(P 5+)O-4, where the curly brackets indicate nine or eightfold coordination, the square brackets sixfold octahedral coordination and the parentheses fourfold tetrahedral coordination. Different isovalent and aliovalent substitutions in a given structure is quite interesting. The KTP-type structure is extremely accommodating with respect to partial or complete isomorphous substitution which may be especially significant in optical devices such as waveguides. A monographic review of the structure-property relationship of KTP isomorphous substitution is briefly and precisely presented. It is shown that the properties of KTP are very sensitive to its structure. Among the composition, structure and properties of KTP-type crystal, the structure is the core because it is a link between the composition and properties.

关键词： potassium titanyl phosphate (KTP) crystal structure and property isomorphous substitution.

Recent Progress on COS-derived Polymers

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Chinese Journal of Polymer Science 2019年第10期37卷 951-958,I0002页

作者： Cheng-Jian zhang Xing-hong zhang Key Laboratory of Macromolecular Synthesis and Functionalization (Ministry of Education) Department of Polymer Science & Engineering Zhejiang University

The synthesis of sulfur-containing polymer, a very promising functional material, has made a great progress in the past several years. This review is focused on the very recent advances in poly(monothiocarbonate)s derived from carbonyl sulfide(COS) and epoxides including biomass-derived epoxides. Of significance, metal-free catalyst systems, including triethyl borane/Lewis base pair and thiourea/Lewis base pair are developed for the alternating copolymerization of COS with epoxides. Thereof, the thiourea/Lewis base pair is highly active to the copolymerization of COS with epoxide in a living manner. Moreover, a series of crystalline poly(monothiocarbonate)s are presented, including the copolymers derived from COS with oxetane, ethylene oxide, enantiopure epichlorohydrin, and achiral mesoepoxides via enantioselective copolymerization. Based on these COS/epoxide copolymerization process, a variety of COS-based block copolymers with well-defined structure are presented.

关键词： Carbonyl sulfide Epoxide Copolymerization Poly(monothiocarbonate)

Special Issue:Rare earth luminescent materials

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Light(Science & Applications) 2022年第10期11卷 2251-2253页

作者： hongjie zhang hong zhang State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchunJilin 130022China Department of Chemistry Tsinghua UniversityBeijing 100084China Van't Hoff Institute for Molecular Sciences University of AmsterdamP.O.Box 941571090 GD AmsterdamThe Netherlands

Trivalent rare earth ions(Ln3+)have the unique elec-tronic configurations[Xe]4fn(n=0-14)and numerous energy levels,which endow rare earth luminescent mate-rials with many fascinating optical properties over a broad spectral region ranging from the ultraviolet(UV)to the near infrared(NIR);these include tunable atomic-like excitation/emission spectra,large Stokes/anti-Stokes shifts,long luminescent lifetimes,and excellent photostability1-4.

关键词： earth luminescent rare

Dual cooperative organocatalysts for one-pot synthesis of polyester-polythiocarbonate block copolymers from multiple monomers

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Science China Chemistry 2020年第12期63卷 1807-1814页

作者： Cheng-Jian zhang Xun zhang Xing-hong zhang Key Laboratory of Macromolecular Synthesis and Functionalization Ministry of EducationDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

The sequential arrangement of multiple monomer units in a polymer chain remains a major challenge in synthetic *** we describe a versatile route to the novel polyester-polythiocarbonate block copolymer from commercially available lactones, epoxides, and carbonyl sulfide(COS). A bicomponent organocatalyst combining triazabicyclodecene(TBD) with triethyl borane(TEB) generates two types of tunable active sites, i.e., TBD-capped alcohol via hydrogen bond and TEB-capped alcohol via O→B coordination bond, which can successively catalyze ring-opening polymerization of lactones and ring-opening copolymerization of COS and epoxides from mixed monomers in one pot. Because of the reversible activated propagating anions and fast activity exchange between the active and dormant species, all of the polymer chains are enchained with both polyester and polythiocarbonate blocks. Kinetic determination quantitatively confirms the proposed mechanism. This method enables diverse lactones and epoxides to form sulfur-containing block copolymers with readily tunable structures.

关键词： block copolymer polyester polythiocarbonate organocatalysis polymer synthesis

The role of ALDH2 in tumorigenesis and tumor progression:Targeting ALDH2 as a potential cancer treatment

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Acta Pharmaceutica Sinica B 2021年第6期11卷 1400-1411页

作者： hong zhang Liwu Fu State Key Laboratory of Oncology in South China Collaborative Innovation Center for Cancer MedicineGuangdong Esophageal Cancer InstituteSun Yat-sen University Cancer CenterGuangzhou510060China

A major mitochondrial enzyme for protecting cells from acetaldehyde toxicity is aldehyde dehydrogenase 2(ALDH2).The correlation between ALDH2 dysfunction and tumorigenesis/growth/metastasis has been widely *** low or high ALDH2 expression contributes to tumor progression and varies among different tumor ***,the ALDH2*2 polymorphism(rs671) is the most common single nucleotide polymorphism(SNP) in *** studies associate ALDH2*2 with tumorigenesis and *** study summarizes the essential functions and potential ALDH2 mechanisms in the occurrence,progression,and treatment of tumors in various types of *** study indicates that ALDH2 is a potential therapeutic target for cancer therapy.

关键词： ALDH2 Polymorphism Cancer Tumorigenesis Progression Cancer therapy Acetaldehyde Metastasis